<template>
  <div>
    <!-- 面包屑导航区 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 警告区域 -->
      <el-alert title="注意：只允许为第三级分类设置相关参数!" type="warning" show-icon 
      :closable="false"></el-alert>

      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>

          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            v-model="selectedCateKeys"
            :options="commodityData"
            :props="cateProps"
            @change="handleChange"></el-cascader>
        </el-col>
      </el-row>

      <!-- tab 页签区域 --> 
      <el-tabs v-model="activeName" @tab-click="handleTapClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled"
            @click="addDialogVisible = true">添加参数</el-button>
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染tag标签 -->
                <el-tag v-for="(item ,i) in scope.row.attr_vals" :key="i" closable
                  @close="handleClose(i, scope.row)">{{item}}</el-tag>
                
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" 
                  @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="small" 
                  @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="small" 
                  @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 静态属性的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled"
            @click="addDialogVisible = true">
          添加属性</el-button>
          <!-- 静态参数表格 -->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染tag标签 -->
                <el-tag v-for="(item ,i) in scope.row.attr_vals" :key="i" closable
                  @close="handleClose(i, scope.row)">{{item}}</el-tag>
                
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" 
                  @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="small" 
                  @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="small"
                  @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 新增属性对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%"
      @close="addDialogClosed()"
    >
    <!-- 添加参数的对话框 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" 
        label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams()">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改属性对话框 -->
    <el-dialog
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%"
      @close="editDialogClosed()"
    >
    <!-- 修改参数的对话框 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" 
        label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams()">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data(){
    return{
      // 动态参数的数据
      manyTableData: [],
      // 静态属性的数据
      onlyTableData: [],
      // 商品分类数据
      commodityData: [],
      // 级联选择框的配置对象
      cateProps: {
        expandTrigger: 'hover',
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 级联选择框双向绑定到的数组
      selectedCateKeys: [],
      // 被激活的页签名称
      activeName: 'many',
      // 控制添加对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm: {
        attr_name: ''
      },
      // 添加表单的验证规则对象
      addFormRules: {
        attr_name: [
          {required: true, message: '请输入参数名称', trigger: 'blur'}
        ]
      },

      // 修改参数
      // 控制修改对话框的显示与隐藏
      editDialogVisible: false,
      // 修改的表单数据对象
      editForm: {},
      // 修改表单的验证规则对象
      editFormRules: {
        attr_name: [
          {required: true, message: '请输入参数名称', trigger: 'blur'}
        ]
      }
    }
  },
  created(){
    this.getCateList()
  },
  methods:{
    // 获取商品选择分类的接口
    async getCateList(){
      const {data: res} = await this.$http.get('categories')
      if(res.meta.status !== 200){
        return this.$message.error('商品选择分类请求失败!')
      }
      this.commodityData = res.data
      console.log(this.commodityData)
    },
    // 级联选择框选中项变化，会触发这个函数
    handleChange(){
      this.getParamsData()
    },
    // tap 页签点击事件的处理函数
    handleTapClick(){
      console.log(this.activeName)
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData(){
      // 证明选中的不是三级分类
      if(this.selectedCateKeys.length !== 3){
        this.selectedCateKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      console.log(this.selectedCateKeys)

      // 证明选中的是三级分类
      // 根据所选分类的id,和当前所处的面板，获取对应的参数
      const{data: res} = await this.$http.get('categories/' + this.cateId +'/attributes',{params: {sel : this.activeName}})
      if(res.meta.status !== 200){
        return this.$message.error('获取参数列表失败')
      }

      // 循环 tag 信息
      res.data.forEach(item => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制文本框的显示与隐藏
        item.inputVisible = false
        // 文本框输入的值
        item.inputValue = ''
      });

      console.log(res)

      if(this.activeName === 'many'){
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }

    },
    addDialogClosed(){
      this.$refs.addFormRef.resetFields()
    },
    // 添加动态参数和静态属性方法
    addParams(){
      this.$refs.addFormRef.validate(async valid => {
        // 验证失败，直接取反
        if(!valid) return
        const{data: res} = await this.$http.post('categories/'+ this.cateId + '/attributes',
          {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          }
        )
        if(res.meta.status !== 201){
          return this.$message.error("添加参数失败")
        }

        this.$message.success('添加参数成功')
        this.addDialogVisible = false
        this.getParamsData()  //刷新数据列表
      })
    },
    // 点击编辑按钮，展示编辑对话框
    async showEditDialog(attrId){
      // 查询当前参数的信息
      const{data: res} = await this.$http.get('categories/'+ this.cateId + '/attributes/' + attrId,
      {params: {attr_sel : this.activeName}})
      if(res.meta.status !== 200){
        return this.$message.error('查询信息失败')
      }
      this.editForm = res.data
      this.editDialogVisible = true
    },
    // 重置修改的表单
    editDialogClosed(){
      this.$refs.editFormRef.resetFields()
    },
    // 点击确定，保存编辑对话框
    editParams(){
      this.$refs.editFormRef.validate(async valid => {
        if(!valid) return
        // 校验成功，发起请求
        const{data: res} = await this.$http.put('categories/'+ this.cateId + '/attributes/' + this.editForm.attr_id,
        {attr_name: this.editForm.attr_name, attr_sel:this.activeName})
        if(res.meta.status !== 200){
          return this.$message.error('修改参数失败！')
        }

        this.$message.success('修改参数成功！')
        // 刷新列表
        this.getParamsData()
        this.editDialogVisible = false

      })
    },
    // 根据ID删除对应的参数项
    async removeParams(attrId){
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)

      // 用户取消了删除操作
      if(confirmResult !== 'confirm') {
        return this.$message.info('已取消删除！')
      }

      const{data: res} = await this.$http.delete('categories/' + this.cateId +'/attributes/' + attrId)
      if(res.meta.status !== 200){
        return this.$message.error('删除参数失败！')
      }
      this.$message.success('删除参数成功!')
      this.getParamsData()
      this.editDialogVisible = false
    },
    // 文本框失去焦点，或按下 回车键
    async handleInputConfirm(row){
      if(row.inputValue.trim().length === 0){
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 如果没有return，则证明输入的内容，需要后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false

      // 发起网络请求，把添加的数据，上传到服务器
      this.saveAttrVals(row)
    },

    // 将对 attr_vals 的操作，保存到数据库
    async saveAttrVals(row){
      // 发起网络请求，把添加的数据，上传到服务器
      const{data: res} = await this.$http.put('categories/'+ this.cateId +'/attributes/' + row.attr_id,
      {attr_name: row.attr_name,
       attr_sel: row.attr_sel,
       attr_vals: row.attr_vals.join(' ')})

      if(res.meta.status !== 200){
        return this.$message.error('修改参数项失败！')
      }

      this.$message.success('修改参数项成功')
    },
    // 点击按钮，展示文本输入框
    showInput(row){
      row.inputVisible = true
      // 让文本框自动获得焦点
      // $nextTick 方法的作用，就是当页面上元素被重新渲染之后，才会指定回掉函数中的代码
      this.$nextTick(_ => {
          this.$refs.saveTagInput.$refs.input.focus();
      });
    },
    // 删除对应的参数可选项
    handleClose(i, row){
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row)
    }
  },

  // 计算节点
  computed: {
    // 如果按钮需要被禁用，则返回true,否则返回false
    isBtnDisabled(){
      if (this.selectedCateKeys.length !== 3){
        return true
      }
      return false
    },
    // 当前选中的三级分类的ID
    cateId(){
      if(this.selectedCateKeys.length === 3){
        return this.selectedCateKeys[2]
      }
      return null
    },
    // 动态计算标题的文本
    titleText(){
      if(this.activeName === 'many'){
        return '动态参数'
      }
      return '静态属性'
    }
  }
}
</script>

<style scoped>

.cat_opt{
  margin: 15px 0;
}

.el-tag{
  margin: 5px;
}

.input-new-tag{
  width: 120px;
}

</style>